Japan's New "Taigei" Submarine Is a Force Multiplier in the Indo-Pacific

January 16, 2025 Topic: Naval Warfare Region: Indo-Pacific Blog Brand: The Buzz Tags: JapanJSDFJapanese NavySubmarinesArea Denial

Japan's New "Taigei" Submarine Is a Force Multiplier in the Indo-Pacific

These submarines are some of the most sophisticated systems ever built by a modern navy and will be a true challenger to China’s naval buildup

 

Japan is making bold moves to change its anti-war culture. That’s not by choice. It’s out of necessity. Japan’s Maritime Self-Defense Force (JMSDF) is enhancing its size and capabilities because Tokyo fears that China’s military growth over the last decade is becoming a direct threat to Japan. 

 

One such system that the Japanese are building a small fleet of Taigei-class (known in Japan as 29SS) attack submarines. It means “Big Whale” in Japanese and is an evolution from the Sōnyū-class submarines. The new sub incorporates lessons learned and technological advancements from the older Sōnyū-class.

Indeed, the Japanese have equipped these submarines with lithium-ion batteries, which both enhances Taigei-class submarine stealth (such power centers are extra quiet when underwater) and allow for greater endurance over other non-nuclear battery systems. 

Crucially to the United States, Japanese defense planners have claimed that their new Taigei-class submarines are specifically intended to counteract China’s aggressive anti-access/area-denial (A2/AD) capabilities. Beijing has arrayed these systems across the arc of the Indo-Pacific, notably in places like the South China Sea. However, China is also prepared to deploy them from its coastal areas to the East China Sea and the Sea of Japan, where they pose a true threat to US military power projection.